Liquid sprayers have long been used to apply liquid to crops, agricultural land, and recreational land for a variety of reasons. For example, pesticides (e.g., herbicides, insecticides, fungicides, and other biocides) are often applied to reduce or eliminate unwanted biological pests from agricultural and recreational land. Similarly, fertilizers, biostimulants, plant growth regulators, and other nutritional products may also be applied by a liquid sprayer to promote growth of desired plant life. Turf paint or dyes may also be applied by a liquid sprayer in order to provide a desired look or aesthetic to a surface.
A common method of applying liquid is by use of a control droplet applicator (CDA), also known as a rotary atomizer. Examples of CDAs for use in a variety of applications may be found in U.S. Pat. Nos. 3,063,644 and 4,225,084, each issued to Edward J. Bals. A CDA generally includes a disc and/or cone with miniaturized teeth at the outer perimeter of the disc and/or cone. In operation, the disc and/or cone rotates and is supplied a fluid to be sprayed. Under the centrifugal force of the rotating disc and/or cone, the fluid migrates towards the periphery of the disc and/or cone and towards the miniaturized teeth. The fluid then comes into contact with the miniaturized teeth and the fluid is sheared into many small droplets. The creation of multiple small droplets may allow efficient application of chemicals to plants (e.g., decreased chemical usage, decreased chemical runoff, and better coverage than traditional pressure-based liquid sprayers). In many applications, CDAs are designed to create droplets of a substantially uniform diameter and/or to apply the droplets in a substantially uniform manner upon the target plant and/or area.
To spray large areas, vehicles have been configured to carry or otherwise convey one or more CDAs to be used according to their desired application. For example, U.S. Design Pat. No. D523,447 sets forth a sprayer assembly for use in applying chemicals over a large area, for example onto golf course fairways and driving ranges or athletic fields.
However, traditional vehicles and apparatuses are not suitable for many applications. For example, residential yards and landscapes may be sensitive to traditional machinery, which often is heavy due to its construction and the incorporated weight of the liquid to be applied. As another example, the soil and grass making up golf greens often is meticulously landscaped to provide a suitable putting surface for golfers. Accordingly, performance of golf greens may suffer tremendously from compaction caused by traditional heavy spraying equipment.
In prior attempts to overcome this limitation, a spraying system including a boom apparatus is often used. In such a system, a spray boom is coupled by a hose to a traditional vehicle holding the liquid to be sprayed. While this arrangement reduces system weight at the point of spraying, such a boom apparatus is often cumbersome and expensive to use. The system often requires additional labor, i.e., multiple persons to walk the spray boom across the green to apply the desired chemical without damage to the green. Moreover, it applies products at traditional higher volumes. unlike the CDA technology. Other approaches to applying chemicals to a green using CDAs or other spray heads have also been too heavy or have proven difficult to operate or maneuver efficiently.
Accordingly, a need has arisen for a lightweight, easily maneuverable apparatus that permits uniform application of liquids using CDAs and other spray heads.